Screenwriter Erik Wolpaw, who contributed to Portal and Portal 2 stated that it has a “pretty cool” starting point for Portal 3. He spoke about this during a conversation on the DidYouKnowGaming YouTube channel.
He came up with this concept together with writer Jay Pinkerton (Jay Pinkerton) – a fellow screenwriter on Portal 2. The idea was even discussed in Valve, although it is not yet clear what stage the consideration is at.
Jay and I have an idea that we think is pretty cool. We don’t have a script or fleshed out details, but we have a kind of premise that we really like.
At the same time, the screenwriter said that much remains to be done so that the third part of the game will be released. You also have to find a team in Valve itself that wants to take on the project. Walpo also indicated earlier that he is ready to work on the third part. Now you can turn your mess into a 3D model
Source: VG Times